McLaren racing director Eric Boullier remains positive about the potential of the MCL33, though admits the team is "not 100%" ready for the Australian GP.
After switching to Renault engines for this season, the Woking-based team was expected to have a much less eventful pre-season than in recent years but, instead, several failures over the eight days means questions do remain going into the first race in Melbourne.
One such question is whether McLaren, who faced a tight schedule to adapt their car to the French engine, has been too aggressive but Boullier insists there was no point in playing safe.
"We want to be competitive and we are ambitious," he told Autosport. "We have an ambitious design around the car and you can see that the car is a little bit different from the other Renault-engined cars.
"So far we had minor issues but I think that was because we didn't do a good enough job to prepare the car."
The main issue McLaren had in Barcelona was with cooling, as overheating led to electrical shutdowns before oil leaks forced Fernando Alonso to stop on track both on Wednesday and Friday.
An upgrade is expected for the first race in just over two weeks but Boullier concedes the interrupted running has left the team slightly on the back foot.
"Not 100% because we have not run as much as we wanted, so there will be a higher risk of failure somewhere," he said of their readiness for Australia.
"Nevertheless we had only minor issues which were all different. A good rebuild of the car for Australia will help us to fix a few issues."
As for the potential competitiveness of McLaren, hopes of challenging Red Bull and the other top teams currently seem too much but the Frenchman isn't counting the team out.
"Let's wait and see," he said. "If you judge based on a few issues on three days, it is better to wait a few races.
"Like anything, you don't do it in one day and there are maybe a few glitches. We have not lost our capability of designing fast cars and I hope you will see it on track soon."
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